Adults overwinter and seek shelter under dead leaves, vines, rocks and other garden debris. As temperatures begin to warm in the spring (late May and early June), squash bugs emerge and fly into gardens where they feed and mate. Egg laying soon begins and continues until midsummer with females depositing small brown eggs usually on the undersides of leaves. Eggs hatch in one to two weeks and the young nymphs disperse quickly to feed. Nymphs pass through 5 instars requiring up to 6 weeks to develop into adults. There is typically one generation per year.
Note: Because of the long egg laying period, all stages of this garden pest occur throughout the summer.
Squash Bug Control
• Plant resistant varieties when available.
• If only a few plants are affected, handpick all stages from the undersides of leaves.
• Place boards or shingles on the ground near host plants. Used as a nighttime shelter, they make excellent traps for morning collecting.
• Floating row covers are extremely effective when placed on seedlings and left in place until plants are old enough to tolerate damage.
• Diatomaceous earth, a natural pesticide made from the fossilized shells of one-celled organisms called diatoms, is abrasive to many insects and can be dusted over plants to reduce numbers.
• If pest levels become intolerable, spot treat with an organic insecticide.
• Roto-till or dispose of infested crop remnants shortly after harvest to reduce overwintering adults.
Molly concludes: Adults do manage to overwinter in our garden. Sounds like hand picking the eggs is a good strategy if we do it every garden day because the eggs need 1-2 weeks to hatch.